import java.sql.*;

public class Main {
    public static void main(String[] args) {
        //jdbc步骤
        Connection connection = null;
        PreparedStatement preparedStatement = null;
        ResultSet resultSet = null;
        try {
            Class.forName("com.mysql.cj.jdbc.Driver");
            String url = "jdbc:mysql://127.0.0.1:3306/jdbc?characterEncoding=utf-8";
            try {
                connection = DriverManager.getConnection(url, "root", "3390956");
                // if(connection != null){
                System.out.println("连接成功");
                // }
                //3.sql
                String sql = "select * from user";
                //4.预编译sql
                preparedStatement = connection.prepareStatement(sql);
                resultSet = preparedStatement.executeQuery();
                //6.
                while (resultSet.next()) {
                    int id = resultSet.getInt(1);
                    String name = resultSet.getString(2);
                    String pass = resultSet.getString(3);
                    System.out.println(id + "----" + name + "----" + pass);
                }
            } catch (SQLException e) {
                throw new RuntimeException(e);
            }
        } catch (ClassNotFoundException e) {
            throw new RuntimeException(e);
        } finally {

            try {
                if (resultSet != null) {
                    resultSet.close();
                }
                if (preparedStatement != null) {
                    preparedStatement.close();
                }
                if (connection != null) {
                    connection.close();
                }
            } catch (SQLException e) {
                throw new RuntimeException(e);
            }
        }

    }
}


